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General tips for my first RDWC

Hello everyone 


Just looking for any info or tips as I start my first RDWC,i have grown in soil and coco for many years but this all new to me to say the least.

I have a 4 pot system 34 ltr tubs 2 nice leds temp stay at 70 during lights out and never above 85 when on well ventilated also running a chiller 19c with a nutrient tank feeding the main pot.

Ok my nutes are at 150ppm with 5.8 to 6.2 ph water temp is a steady 68f.


Its been running now for 5 days plants look good if not a little slow in taking off my main problem is ph drifting I set the ph at 5.8 and it drifts right threw to 6.3 then I readjust just wondering is this normal for the start ?

Also im a bit worried about the first nutrient change so any info or tips will be gratefully took on board.

thanx all :thumsup:

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Hi mate.

Sounds like you've done your research and also spent a few quid!!!

What nutes you using?

I operate in ec and with young plants would be around 0.8ec.

My tips would be keep it simple,don't piss about with additives.

Hand water a couple of times a day till your roots hit the solution.

Once your roots are established Allow your solution to drop to about halfway down the bucket before topping up...it's my opinion this is where you get the best growth from dwc as the roots in the gap (100% humidity)are effectively operating like aeroponics.

Your ph will settle soon if your at the right ec.

If your ph drops your nutes are too strong,if it's going up then your nutes are too weak.

This is advice for when the roots are in the drink...Not the first week or so.

Lastly...put up a thread and the other dwc heads will guide you if you need it.

There's a few I would listen to the most...

Me ( lol ) stu914 and bad billy bud


As for nute changes as I'm in a loft I syphon with a hosepipe into the bathroom below.

If this don't float yer boat use the recirculation pump (if you have one) to pump it out.

You don't have to get every last drop out so don't sweat the small stuff.

Good luck 

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thx pal for replying 


my nutes are plantmagic DWC A and B root stim -pure clean- hydro silicon and enzyme that's it really and 0.8 ec is like 400 ppm at the 500 scale so im running roughly half of what u sugest I also started the plants from seed so as soon as they shown they was put in the system its been slow but everything seems ok but if what u sugest 0.8 ec to start im well under feeding !


And yea that was why I was worried I can drain the system out no problem to just under the outlet pipes but that leaves like 2 inch of water in each pot was worried about leaving that much water still in !

Also am getting a residue left behind off the root stimulator is this normal ? 

like I said earlier im like a new born child with hydro so its a completely different thing im use to all the help is so appreciated :)

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Hi man. I’m on my 3rd go at dwc. What’s the background ec of your water? I’m in a soft water area. Ec almost 0. So I use cal mag in my mix. Good shout already about @stu914 and @badbillybob  check out badbillybob’s diary in his diy rdwc system. Awesome!!

@stu sleeper 20vt great shout on the siphon into the bathroom below. My backs gonna thank you for that one. Can’t believe I didn’t think of it sooner. Do you pump up into the loft also? Or use the water tank that’s up there? 

Sorry to highjack your thread @mactryer and good luck with the grow. 

Edited by The Padawan
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That's np pal

So if my ph is soft which it is it doesn't even register on my blue lab guardian I need to add cal mag ? 

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what is your ph out of the tap water?

when you say your water is soft, it would be taken from the ec reading, so I take it you mean ec?

if your ec is at 0.2  or lower, you will have to add cal mag. The plants don't generally show signs of deficiency till a couple of weeks into bloom, but it is better to give a low dose during veg, even 0.25ml per litre to 0.5 ml per litre.

also do the same dose of silicone during veg and up until about 3 weeks into bloom, and then stop the silicone.


Also, carefully check your root stim, and if has anything organic in it, don't use it, it will cause loads of issues. what make of root stim is it?


oh and I start mine at 0.6 ec, you have 150ppm which is about the equivalent of 0.3, so you could safely up it to 0.6/0.8 ec. 


Edited by badbillybob
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hey and thx for replying


My ph out of the tap is 6.7 with a blank reading on my nutrient meter.

I checked my root stimulant but it has nothing on it relating to ingredients as such its Plantmagic root stimulant.

And yea I was saying EC cos the chap before who commented said he only used EC personaly I use the ppm meter 500 scale.

im very new to this type of growing so I just used all the same brand of food, silicone etc and its all plantmagic I am also very new to forums first time on a forum.


What type of food, root stim, silicone is best do you think I only used plantmagic as it was the only one I could find that's specifically targeted to DWC.  

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@The Padawan Yeh mate I fill them from the bathroom tap with the same hose then ec/ph but I've been doing the same shit so long I know pretty much what to add.



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